Process of pressure distillation



. R. J. BLACK PROCESS OF PRESSURE DISTILLATION Filed April so 1921 i 2 Sheets-Sheet 1 lmfemfori m 7, 11924v 151mm I R. J. BLACK PRGCESS OF PRESSURE DISTILLATION Filed April 30 1921 2 Sheets-Sheet 21 afz'imess:

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Patented @ct. 7, i924.

urea srnrns ROBERT 5. BLACK, or KANSAS GITY, KANSAS.

PROCESS PRESSURE DISTILLATION.

I v Application filed April 30, 1921. Serial No. 465,874.

ject the cracking or splitting up of heavier hydrocarbons, such as are contained in gas oil and crude petroleum, for the purpose of forming gasoline or other lighter or more volatile products. For this purpose the oil is heated to a high temperature under a pressure, ordinarily of four or five atmospheres, with the result that certain of the hydrocarbons constituting the gas oil or thelike are broken down and vaporized, the vapors thereof being collected and condensed and further treated for the purpose of forming a commercial gasoline. The apparatus commonly employed for this purpose comprises an externally heated still drum or shell in which the oil is heated under pressure to the crackingtemperature and from. which the vapors formed are led to a tower in which the heavier. hydrocarbons are condensed, the lighter hydrocarbons forming the desired distillate passing by a vapor-line to a condenser and thence to a run-downdrum or condensate receiver. The latter is commonly provided with a connection by which the fixed gases, formed during the distillation are led away or permitted to escape.

The use of the method commonly em.- ployed today results in the formation, in addition to the gasoline, of free carbon or coke and non-condensable or fixed gases. The carbon or coke is drawn off with the heavierresidue from the operation,constituting practically a waste product and the fixed gases are ordinarily burned or a certain rop-ortion of them absorbed in heavy oil. dhese fixed gases ordinarily constitute from two to ten per cent of the roduct and are practically a refining loss. t is the purpose of my invention to utilize these noncondensable gases, returning them to the still, incorporating them with the distillate chemically thereby increasing the amount and improving the quality of the gasoline produced, and making pressure distillation a more profitable method of manufacture.

compressor and the exhaust side of the latter is connected to a perforated pipe or system of pipes located in the bottom or other portion of the pressure still where the oil is in direct contact with the highly heated wall thereof and where cracking of the oils and vapors, consequently, largely takes place. The fixed gases containin a large amount of available hydrogen being thus injected into the oil under pressure and into direct contact with the hydrocarbons including the newly formed or nascent'un saturated hydrocarbons, supply the latter with hydrogen so that a larger proportion of saturated and more hearl saturated hydrocarbons are formed. o-reover, by thus saturating the, oil in the region of active decomposition and recomposition with highly compressed fixed gases the further formation of the latter is opposed under the well-known law of mass action, while permitting and assisting the formation of the more desirable hydrocarbons.

In the accompanyin drawing I have shown and in the following specification described a preferred form of apparatus for practicing my invention; it'is tobe understood, however, that the invention is not limited to the specific form of apparatus employed, nor to the particular type of still shown, it being applicable to substantially. all shell types of pressure stills.

In the accompanying drawingsFig. 1 is a 1 partially diagrammatic side elevation of a still with its connections, embodying my inf vention; Fi 2a plan view showing two of the units 0 a battery of such stills, partly broken away to. show their construction; Fig. 3 a front elevation thereof; Fig. 4: a transverse section of a still'embodying my invention, on an enlarged scale; Fig. 5 a longitudinal vertical section through such still showing a specifically difi'erentform of tower and run-back; Fig. 6 an enlarged diagrammatic view of a compressor and its connections; and Fig. 7a similar view of a preferred form of release manifold.

Each part is identified by the same refer- I ence character wherever it occurs in the several views.

My invention belng applicable to shell is conducted to a manifold 26.

stills in general, I have chosen to illustrate it in connection with a well known form of equipment, the essential elements of which T will now proceed to briefly identify, it being observed that the several units of the battery of stills partially shown are substantially identical and therefore a description of one will sufficefor both. .The still shown is ofthe. shell type, and comprises a retort or shell 6, furnacesetting 7 and tower 8. The shell vis provided with a safety valve 6 to prevent excess pressure therein and a draw-off a for emptying the still. in the form of the device shown in'T igs. 1 to 3 inclusive the tower is supported by frame work 9 and connected to the shell or still proper by the mainvapor line 10, and from the upper end of the tower a vapor-line 11- descends to a T 12 connected on the one side by an auxiliary "'rundoack 13 to the main run-back 10 and on the other side by the vapor-line 14 to the condenser 15. 0n its way to the condenser this'vapor-line is car-- ried through the pressure control house 16 where it is provided with pressure-gauge and valve regulation. Each condenser is connected by a run-down line 17 with a rundown drum 18 to receive the condensate and the run-down drums are connected to a common gas-line 20 by pipes 19, 19, by

which the fixed-gas is led away from such connected by pipes 22 to the intakes of coinpressors 23, respectively, and the outlets of the latter are connected by pipes 2%, respectively, to a high pressure gas-line 25 by which the fixed gas, after'being compressed, Manifold 26 extends over the drums of the battery and'is formed or provided witha series of branch pipes 27 through which the fixed gases are led to pipes 28 located in the bottoms of the shells and perforated so as to inject the gasesinto the liquid and against the bottom of the still over substantially all of the heated area thereof. The perforated pipe 28 may be duplicated or multiplied in the still.

In case itis desired to introduce steam with or without the fixed gas, I have, shown at 29 a steam pipe which is connectedat 30 to the manifold. 1

The operation of the apparatus will be apparent from the above description thereof. The vapors and gases developed in each still pass through the main vapor line to the towers, in which, as usual, the heavier hydrocarbons which are not light enough to be included in the desired distillate are con- .tive stills.

densed and returned to the still. From the upper end of the tower the vapors which are "to form the distillate together with what "fixed gases are formed pass by vapor-lines 11, 14 through the pressure control house and to the respective condensers." From the condensers the condensate and the uncondensed gases pass to the run-down drums 18 from which the fixed gases are delivered by pipes .19, 20 to the gas receiver 21. The pipes. 19 connecting the run-down drums with the low pressure pipe 20 are provided with suitable valves 19 by which the pressure in the still system may be controlled.

drawn by the compressors and after being put under a pressure in excess of that in the stills areforced through the common From the. gas receiver 21 the gases are gas-line 25, manifold 26, and branch pipes 27, to the perforated pipes 28 in the respec- The gas issuing ,under high pressure and with great velocity from the perforated pipeis directed against or towards the bottom of thestill and particularly towards those portions thereof which are mosthighly. heated. The gas thus in troduced performs'both a chemical and a mechanical function. The heated oil in the region of greatest chemical activity -is saturated with the fixedgas whereby the formation of additional quantities of such gases is opposed. Moreover, the presence of the hydrogen Jcontained in'such gases in the reaction zone-increases the saturation of the of the still by the cinculation of the liquid in contact therewith, thus preventing overheating and burning of the still and development'of hot-spots and local overheating. By th continuous introduction of the fixed gases tratification of the gases and vapors within, the still is prevented,

By my improved method of operation the proportion of distillate of the desired composition is increased andzits quality improved, the distillate produced being-nearer than ordinary pressure distillate. More.- over, my improved method of gas injection and circulation renders the control of the pressure in the still positive and .easy, and

it is possible to maintain a materially higher pressure with the same firing of the 'still. lit will be observed, moreover, that the gas receiver floats 'on' thelow pressure line and equalizes fluctuations-on the tow pressure slde. Tn carrying out the 1nvention it is advantageous in addition [to the 'to water-white in color and easier to keep other gases rich in' hydrogen, such for exe ample, as natural gas. F or'this purpose I I'OVldQ a connection 40 with a valve 41 for introducing such gas-intothe. gas receiver.

Fig. 1 are of a round't pe. I refer however, to employ the stituted for t at of Fig. 1. The tower 8 is shown as'connected to a drum 42 onthe still I by a run back 43; ,The vapor line 44 is connear the bottom a cylinder or tube, of

larger diameter 47, the lower 'end of which" is contracted or headed at 48 for connection to a pipe 49' which extends into the still drum and nearly to the bottom of the latter. The upperjend ofthe cylinder or en-- larged pipe 47 is closed at 50 and a vapor line 51 extends therefrom to the cond'ensor,

By meansofv the-construction just described, any-fine drops or particles of condensate formed in the tower v and such condensate v as is formed-in the pipes, 44, 45and 46 isreturned to thedrumz Thevapors' containin such condensate flow downward 1 throug tube 46 .at considerablespeed and emerging down to thebottom of the cylinder- 47 and passed by pipe 49 to th'e'bo'dy of the liquidline ma "from the lower end of pipe46 into cylinder upwardly therein to the vapor 47 'p as'sin' line 51. he heavier drops of condensate however, throughtheirjinertiaare carried in-the drum. By this construction and by properlyproportionin'g'the parts and pressure of regulation it is possible to much more i 1 accurately separate the heavier hydrocar bons from those which are light enough to form part of the desired distillate. j, j x

The compressionand return of the gas from the low pressure. tolthe high pressure he vregulated By controlling the "speed 0 the compressor. Inpractice how-' ever, I have found it more; convenient and practical toeifect the control of the return ofthe gas to the still drum without ,resortj ing to regulation ofxspeed of the compressors by. means of-a'connection shown in Fig.

ormf o apparatus shown in Fi 5 which mayreadily'be' sub-" 7 10 drocarbons at a crac s of the drawing. n' said figure the com I pressor is diagrammaticall re resented at 235, the compressing cylin er eing shown at 52. In thisarrangementofv branch 54 being connected to the intake side of the compress'or. The exhaust side of the compressor is connected by high pressure line. The 0t er branch 55 H rts the pipe, v 22 from the receiver is branc ed at 53, one The tower'8 andvapor .line 11 shown in.

f ro m the .low'pressure line constitutes a by- ."P lS about the compressor and is connected at56 to the-high pressureline 24. Hand valves 57', 58 are included in the respective branches, and a pressure, gauge 59 is included'in the by-pass. B manipulation of the hand valves 57,-58 t e amount of gas that passes through the compressor may be regulated and-excess gas delivered by the compressor returned to the low pressure line. Thus the valve"'adj'ustment of the speed of thecompressor and the amount of gas returned to the still drum may be regu-- lated as required, the-pressure ga einforming the operator of pressure conditions within the line.

a In Fig. 2- I have indicated .dia amniatically the valves 19 which contro the'pressure inthe run-down drums. I prefer, however, for accuracy ot-ad ustment to use the construction shown in 1 7, Instead of employing a single valve provide a plu-' 'rality of needle valves 60;v

three in number, connected across the headere shown as ersj 61,. 62. It will beobvious that these valves maybe of smaller capacity than a v p v the sam'eflow andmore .accurateregulation is therefore single valve for icontrollin possible.

Iclaim:

A process of making gasoline andthe like,

consisting in' heatingfia pressurein anexterna y heated shell still, and continuously injecting highly comof the still shell with which the liquid is in contact, thatis into the region of most ac-' tive decomposition, and" over substantially all 'of th'e heated area thereof. I

" ROBERT JL BLACK,

body] of heavier hy-' n temperature under 

